#33. In two or three well-developed paragraphs, explain how water is treated so that it can be used for safe drinking water. Include definitions of the terms potable and pathogens.

my answer:

There are many steps to how water is treated so that it can be potable, or used for safe drinking water. Water treatment removes harmful elements from the water, such as pathogens, which are organisms that cause illness or disease. The first step is Filtration, this is the first filtration step. In this step, the source water supply is filtered to remove large organisms and trash. In the second step, coagulation, Alum is rapidly mixed into the water and forms sticky globs called flocs. Then, bacteria and other impurities cling to the flocs, which settle to the bottom of the tank. The third step is the second filtration step. In this, the layers of sand, gravel, and hard coal filter the remaining impurities. Chlorination is the fourth step of water treatment. During this step chlorine is added to prevent bacteria from growing in the water. In the fifth step, aeration, air is forced through the water to release unwanted gases. This reduces odor and improves taste. The last step of the water treatment process is additional treatment. In some communities, fluoride may be added to prevent tooth decay. Sodium compounds or lime may also be added to soften hard water. Finally, the treated water is then pumped from storage tanks to homes and businesses.

How's this?

most water must be treated to make it potable or safe to drink.

Your response provides a good overall explanation of the process of water treatment to make it safe for drinking, including the key steps involved. However, in order to improve the quality and clarity of your explanation, I would suggest making a few tweaks:

"There are several crucial steps involved in treating water to make it potable, which refers to its suitability for consumption without causing harm. Pathogens are microorganisms that can lead to illness or disease. The first step in the water treatment process is filtration. During this initial phase, the source water supply is passed through filters to remove large debris and organisms.

The next step is coagulation, where a substance such as alum is added to the water. This causes tiny particles to clump together, forming larger masses called flocs. These flocs trap bacteria and other impurities, aiding in their removal during the sedimentation process. In sedimentation, the water is allowed to sit in large tanks, allowing the flocs to settle at the bottom.

After sedimentation, the water undergoes a second filtration stage. This process involves passing the water through layers of sand, gravel, and activated carbon, which capture any remaining impurities. Chlorination is then employed to kill or inactivate any remaining microorganisms. Chlorine is added in carefully controlled amounts to prevent the growth of bacteria in the treated water.

To improve the taste and odor of the water, aeration is performed. Air is forcefully introduced into the water, causing unwanted gases to be released. In some regions, additional treatment steps may follow, such as the addition of fluoride to prevent tooth decay or the use of sodium compounds or lime to soften hard water.

Once all these steps are completed, the treated water is pumped from storage tanks to homes and businesses for safe consumption. This comprehensive process ensures that the water is free from harmful pathogens and other contaminants, meeting the required standards for potable water."

By making these adjustments, your explanation becomes more thorough, precise, and informative.